In a conventional glass fiber forming operation, a container referred to as a bushing is used to hold molten glass. The bottom of the bushing contains a plurality of nozzles or tips having a cone-like shape called a bushing tip plate from which the molten glass is drawn to be formed into multiple thin streams of glass. The glass stream flowing through the nozzles are attenuated by gathering them into a strand at a gathering point and winding them on a conventional rotating cylindrical winder.
The conventional glass fiber forming operation also includes the utilization of fin blade assemblies to cool the bushing tips. The fin blade assembly is generally comprised of a plurality of fins that extend from a manifold between adjacent rows of tips in the bushing tip plate. The manifold contains a heat transfer medium, such as a fluid and/or air stream as well known in the art, so that heat can be removed from the surface of each of the fins to the manifold so as to cool the nozzles directly below the tip plate and maintain the tip plate at a desired temperature during the glass fiber forming operation.
Dual manifold assemblies may be utilized in a conventional glass fiber forming operation as described above. In a dual manifold assembly, two manifold members are spaced apart from each other in a horizontal plane and are operatively connected by virtue of the fins extending between each of the manifolds. Each half of the dual manifold assembly is the mirror image of the other. One or more bushing assemblies may be spaced between the manifolds above the fins for cooling the fin plate. For a more detailed discussion of the manufacture of glass fibers, reference is made to U.S. Pat. Nos. 4,018,586 and 4,328,015, incorporated herein by reference.
One of the problem associated with the conventional fin blade assembly is that during the glass fiber forming operation, the fin manifold physically obstructs air flow adjacent the fins resulting in reduced localized heat loss from the tip plate to the fins. It is also a common problem with heretofore known fin blade assemblies that the location of the manifold relative to the fins impedes the visibility of the tip plate thereby preventing inspection of the tip plate during attenuation of the glass fibers.
It is seen then that it would be desirable to have an improved fin blade assembly which allows unimpeded visibility of the tip plate and allows unobstructed cooling air flow across the nozzle tips. Accordingly, an object of the present invention is to provide an improved fin blade assembly for use in producing glass fibers. It is another object of the present invention to provide an improved fin blade assembly by modifying a conventional glass fiber forming apparatus to provide unimpeded air flow and visibility of the tip plate during glass fiber forming. Specifically, and according to the present invention, the manifold is offset from the fin blades so as to allow visibility of the tip plate and unobstructed flow of air through the flow passages between the fin blades during glass fiber forming.